diff --git a/.gitignore b/.gitignore
index 92110594..d46d61f6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 /.idea
 /logs
+/build
 /vendor
 /tmp
 /examples/wordpress
diff --git a/bin/compiler.php b/bin/compiler.php
index 2764eb20..bf21073e 100755
--- a/bin/compiler.php
+++ b/bin/compiler.php
@@ -14,6 +14,11 @@ $path = $argv[1];
 $translator = new Translator(ROOT_PATH);
 $translator->setIndent('    ');
 
+$path = realpath($path);
+if ($path === false) {
+    die("path not exists: $path\n");
+}
+
 if (is_dir($path)) {
     $scanner = new FileScanner($path);
     $list = $scanner->scan();
@@ -26,14 +31,26 @@ if (is_dir($path)) {
 $sourceFiles = [];
 $objectFiles = [];
 
-// 分析 PHP 文件，生成 C++ 文件
+// 分析 PHP 文件，预处理
+foreach ($list as $k => $file) {
+    if (FileScanner::isPhpFile($file)) {
+        try {
+            $translator->prepare($file);
+        } catch (Unsupported $e) {
+            echo " unsupported syntax: " . $e->getMessage() . "\n";
+            echo " skip: " . $file . "\n";
+            unset($list[$k]);
+        }
+    }
+}
+
+$translator->sortFiles($list);
+
+// 生成 C++ 文件
 foreach ($list as $file) {
     try {
         if (FileScanner::isPhpFile($file)) {
-            $code = $translator->convert($file);
-            $info = pathinfo($file);
-            $cppFile = $info['dirname'] . '/' . $info['filename'] . '.cc';
-            $translator->save($code, $cppFile);
+            $cppFile = $translator->convert($file);
         } elseif (FileScanner::isCppFile($file)) {
             $cppFile = $file;
         } else {
diff --git a/examples/project/call.php b/examples/project/call.php
new file mode 100644
index 00000000..f3ced80c
--- /dev/null
+++ b/examples/project/call.php
@@ -0,0 +1,12 @@
+<?php
+function fn1()
+{
+    echo "fn1\n";
+    fn2();
+}
+
+function fn2()
+{
+    var_dump(__FILE__, __DIR__, __LINE__, __FUNCTION__);
+    echo "\n";
+}
diff --git a/examples/project/ext.cc b/examples/project/ext.cc
new file mode 100644
index 00000000..50708651
--- /dev/null
+++ b/examples/project/ext.cc
@@ -0,0 +1,11 @@
+#include <phpx.h>
+#include "phpx_func.h"
+
+using namespace php;
+
+Int php_ext_test(Int a, Int b) {
+    auto c = a + b;
+    var_dump(c);
+    var_dump(php_uname());
+    return c;
+}
diff --git a/examples/project/ext.stub.php b/examples/project/ext.stub.php
new file mode 100644
index 00000000..f106e1be
--- /dev/null
+++ b/examples/project/ext.stub.php
@@ -0,0 +1,4 @@
+<?php
+function ext_test(int $a, int $b): int
+{
+}
\ No newline at end of file
diff --git a/examples/project/main.php b/examples/project/main.php
new file mode 100644
index 00000000..7c0a69d7
--- /dev/null
+++ b/examples/project/main.php
@@ -0,0 +1,6 @@
+<?php
+function main()
+{
+    fn1();
+    ext_test(199, 189);
+}
\ No newline at end of file
diff --git a/src/Php/FileScanner.php b/src/Php/FileScanner.php
index 1e6dcc60..71a051d5 100644
--- a/src/Php/FileScanner.php
+++ b/src/Php/FileScanner.php
@@ -48,6 +48,29 @@ class FileScanner
         return $this;
     }
 
+    public function setExcludePatterns(array $patterns): self
+    {
+        $this->excludePatterns = $patterns;
+        return $this;
+    }
+
+    public function getDirectory(): string
+    {
+        return $this->directory;
+    }
+
+    private function isExcluded(string $filePath): bool
+    {
+        $excluded = false;
+        foreach ($this->excludePatterns as $pattern) {
+            if ($this->matchPattern($pattern, $filePath)) {
+                $excluded = true;
+                break;
+            }
+        }
+        return $excluded;
+    }
+
     public function scan(): array
     {
         $files = [];
@@ -59,20 +82,16 @@ class FileScanner
             if ($file->isFile()) {
                 if (self::isPhpFile($file)) {
                     $filePath = $file->getPathname();
-                    $excluded = false;
-                    foreach ($this->excludePatterns as $pattern) {
-                        if ($this->matchPattern($pattern, $filePath)) {
-                            $excluded = true;
-                            break;
-                        }
-                    }
-                    if (!$excluded) {
-                        $files[] = $filePath;
-                    }
+                } elseif (self::isCppFile($file)) {
+                    $filePath = $file->getPathname();
+                } else {
+                    continue;
+                }
+                if (!$this->isExcluded($filePath)) {
+                    $files[] = $filePath;
                 }
             }
         }
-        sort($files);
         return $files;
     }
 
diff --git a/src/Php/FileSorter.php b/src/Php/FileSorter.php
new file mode 100644
index 00000000..38c21e1e
--- /dev/null
+++ b/src/Php/FileSorter.php
@@ -0,0 +1,94 @@
+<?php
+
+namespace PhpAot\Php;
+
+class FileSorter
+{
+    private array $functionDeclInFile;
+    private array $functionCallInFile;
+
+    public function __construct(array $functionDeclInFile, array $functionCallInFile)
+    {
+        $this->functionDeclInFile = $functionDeclInFile;
+        $this->functionCallInFile = $functionCallInFile;
+    }
+
+    public function sort(): array
+    {
+        $dependencies = $this->buildDependencies();
+
+        $allFiles = $this->getAllFiles();
+
+        $inDegree = array_fill_keys($allFiles, 0);
+        foreach ($dependencies as $deps) {
+            foreach ($deps as $dep) {
+                $inDegree[$dep]++;
+            }
+        }
+
+        $queue = [];
+        foreach ($inDegree as $file => $degree) {
+            if ($degree === 0) {
+                $queue[] = $file;
+            }
+        }
+
+        $sorted = [];
+        while (!empty($queue)) {
+            $current = array_shift($queue);
+            $sorted[] = $current;
+
+            if (isset($dependencies[$current])) {
+                foreach ($dependencies[$current] as $dep) {
+                    $inDegree[$dep]--;
+                    if ($inDegree[$dep] === 0) {
+                        $queue[] = $dep;
+                    }
+                }
+            }
+        }
+
+        if (count($sorted) !== count($allFiles)) {
+            throw new \RuntimeException("Circular dependency of function call detected");
+        }
+
+        return array_reverse($sorted);
+    }
+
+    private function buildDependencies(): array
+    {
+        $dependencies = [];
+
+        foreach ($this->functionCallInFile as $call) {
+            $callerFile = $call['file'];
+            $functionName = $call['name'];
+
+            if (isset($this->functionDeclInFile[$functionName])) {
+                $declFile = $this->functionDeclInFile[$functionName];
+
+                if ($callerFile !== $declFile) {
+                    if (!isset($dependencies[$callerFile])) {
+                        $dependencies[$callerFile] = [];
+                    }
+
+                    if (!in_array($declFile, $dependencies[$callerFile])) {
+                        $dependencies[$callerFile][] = $declFile;
+                    }
+                }
+            }
+        }
+
+        return $dependencies;
+    }
+
+    private function getAllFiles(): array
+    {
+        $files = array_values($this->functionDeclInFile);
+
+        foreach ($this->functionCallInFile as $call) {
+            $files[] = $call['file'];
+        }
+
+        return array_unique($files);
+    }
+}
\ No newline at end of file
diff --git a/src/Php/RedoException.php b/src/Php/RedoException.php
new file mode 100644
index 00000000..67ed9a4f
--- /dev/null
+++ b/src/Php/RedoException.php
@@ -0,0 +1,8 @@
+<?php
+
+namespace PhpAot\Php;
+
+class RedoException extends \RuntimeException
+{
+
+}
\ No newline at end of file
diff --git a/src/Php/ReturnTypeChanged.php b/src/Php/ReturnTypeChanged.php
deleted file mode 100644
index 53e2cf28..00000000
--- a/src/Php/ReturnTypeChanged.php
+++ /dev/null
@@ -1,8 +0,0 @@
-<?php
-
-namespace PhpAot\Php;
-
-class ReturnTypeChanged extends \RuntimeException
-{
-
-}
\ No newline at end of file
diff --git a/src/Php/Translator.php b/src/Php/Translator.php
index 53a9a199..23013578 100644
--- a/src/Php/Translator.php
+++ b/src/Php/Translator.php
@@ -9,10 +9,10 @@ use PhpParser\Node\Expr\Variable;
 use PhpParser\Node\Identifier;
 use PhpParser\Error;
 use PhpParser\Node\NullableType;
+use PhpParser\NodeFinder;
 use PhpParser\NodeTraverser;
 use PhpParser\ParserFactory;
 use PhpParser\PrettyPrinter;
-use SimplePie\Exception;
 use stdClass;
 
 class Translator extends \PhpAot\Core\Translator
@@ -101,6 +101,9 @@ class Translator extends \PhpAot\Core\Translator
     private array $nativeFunctions = [];
     private array $internalFunctions = [];
     private array $nativeConstants = [];
+    private array $functionDeclInFile = [];
+    private array $functionCallInFile = [];
+    private array $redoAfterDeclare = [];
     private int $optimizeLevel = 0;
     private int $floatPrecision = 17;
     private bool $debugInfo = true;
@@ -129,16 +132,19 @@ class Translator extends \PhpAot\Core\Translator
 
     const string PREFIX = 'php_';
     private string $rootPath;
+    private string $buildDir;
     private int $debugLine = 0;
     private CLImate $climate;
     private array $beforeStmtLines = [];
     private array $afterStmtLines = [];
     private bool $inLoop = false;
     private bool $inSwitch = false;
+    private bool $stubFile = false;
 
     public function __construct(string $rootPath)
     {
         $this->rootPath = $rootPath;
+        $this->setBuildDir($rootPath . '/build');
         $climate = new CLImate;
         $this->climate = $climate;
         $climate->arguments->add([
@@ -306,21 +312,32 @@ class Translator extends \PhpAot\Core\Translator
         return $this->genIncludeHeaderFiles() . $this->genExternGlobalVars() . $cppCode;
     }
 
-    public function convert(string $file): string
+    private function removeCommonPrefix(string $str1, string $str2): string
     {
-        if (!file_exists($file)) {
-            throw new \Exception('File not exists: ' . $file);
+        $len = min(strlen($str1), strlen($str2));
+        $prefixLen = 0;
+
+        for ($i = 0; $i < $len; $i++) {
+            if ($str1[$i] === $str2[$i]) {
+                $prefixLen++;
+            } else {
+                break;
+            }
         }
-        $phpCode = file_get_contents($file);
-        $this->file = realpath($file);
-        $this->dir = dirname($this->file);
+        return substr($str2, $prefixLen);
+    }
 
+    public function convert(string $file): string
+    {
+        $phpCode = $this->loadFile($file);
         while (true) {
             try {
-                return $this->doConvert($phpCode);
-            } catch (ReturnTypeChanged $e) {
-                // 某些情况，例如返回值变更，需要重新解析
-                $this->climate->cyan('Return type changed, retrying...');
+                $cppCode = $this->doConvert($phpCode);
+                $info = pathinfo($file);
+                $cppFile = $this->buildDir . '/' . $this->removeCommonPrefix($this->buildDir, $info['dirname'] . '/' . $info['filename'] . '.cc');
+                $this->save($cppCode, $cppFile);
+                return $cppFile;
+            } catch (RedoException $e) {
                 continue;
             }
         }
@@ -328,6 +345,10 @@ class Translator extends \PhpAot\Core\Translator
 
     public function save(string $code, string $file): void
     {
+        $dir = dirname($file);
+        if (!is_dir($dir)) {
+            mkdir($dir, 0777, true);
+        }
         file_put_contents($file, $code);
         $this->formatCppCode($file);
     }
@@ -370,9 +391,8 @@ class Translator extends \PhpAot\Core\Translator
         $this->tmpVarIndex = 0;
     }
 
-    private function parseFunctionDef($v): string
+    private function getFunctionName(Node $v): string
     {
-        $this->resetScope();
         $names[] = $this->parseIdentifier($v->name);
         if ($this->class) {
             $names[] = strtolower($this->class);
@@ -380,20 +400,40 @@ class Translator extends \PhpAot\Core\Translator
         if ($this->namespace) {
             $names[] = strtolower(str_replace('\\', '_', $this->namespace));
         }
+        return implode('__', array_reverse($names));
+    }
 
-        $name = implode('__', array_reverse($names));
+    private function parseFunctionDeclaration(string $name, Node $v): FunctionDef
+    {
+        $functionDef = new FunctionDef();
+        $this->functionDef = $functionDef;
+        $functionDef->name = $name;
+        if ($v->returnType) {
+            $functionDef->returnType = $this->getTypeFromZendType($this->parseIdentifier($v->returnType));
+        } else {
+            // .stub 存根定义 C++ Native 函数，必须设置返回值类型
+            if ($this->stubFile) {
+                throw new Exception('No return type for ' . $name);
+            }
+            $functionDef->returnType = 'void';
+        }
+        $this->parseParams($v->params);
+        return $functionDef;
+    }
+
+    private function parseFunctionDef(Node $v): string
+    {
+        $this->resetScope();
+        $name = $this->getFunctionName($v);
         if (isset($this->nativeFunctions[$name])) {
             $this->functionDef = $this->nativeFunctions[$name];
         } else {
-            $this->functionDef = new FunctionDef();
-            $this->functionDef->name = $name;
-            if ($v->returnType) {
-                $this->functionDef->returnType = $this->getTypeFromZendType($this->parseIdentifier($v->returnType));
-            } else {
-                $this->functionDef->returnType = 'void';
+            $this->nativeFunctions[$name] = $this->parseFunctionDeclaration($name, $v);
+            if (isset($this->redoAfterDeclare[$name])) {
+                unset($this->redoAfterDeclare[$name]);
+                $this->climate->cyan('Received redo request, retrying...');
+                throw new RedoException;
             }
-            $this->parseParams($v->params);
-            $this->nativeFunctions[$name] = $this->functionDef;
         }
 
         foreach ($this->functionDef->argInfoList as $argInfo) {
@@ -482,6 +522,10 @@ class Translator extends \PhpAot\Core\Translator
         $list = [];
         $this->functionDef->argCountRequired = count($params);
         foreach ($params as $param) {
+            // .stub 存根定义 C++ Native 函数，必须设置函数的参数类型
+            if ($this->stubFile and !$param->type) {
+                throw new \RuntimeException('No type for ' . $this->parseIdentifier($param->var));
+            }
             $type = $this->parseType($param->type);
             $name = $this->parseIdentifier($param->var);
             $list[] = $type . ' ' . $name;
@@ -726,11 +770,10 @@ class Translator extends \PhpAot\Core\Translator
             case self::EXPR_VARIABLE:
                 return $this->parseIdentifier($expr);
             case 'Scalar_MagicConst_File':
-                return $this->parseMagicConstFile($expr);
             case 'Scalar_MagicConst_Dir':
-                return $this->parseMagicConstDir($expr);
             case 'Scalar_MagicConst_Line':
-                return $this->parseMagicConstLine($expr);
+            case 'Scalar_MagicConst_Function':
+                return $this->parseMagicConst($expr);
             case 'Scalar_InterpolatedString':
                 return $this->parseInterpolatedString($expr);
             case 'Expr_Cast_Int':
@@ -958,7 +1001,9 @@ class Translator extends \PhpAot\Core\Translator
     private function resetReturnType(string $type): void
     {
         $this->functionDef->returnType = $type;
-        throw new ReturnTypeChanged;
+        // 返回值变更，需要重新解析
+        $this->climate->cyan('Return type changed, retrying...');
+        throw new RedoException;
     }
 
     private function detectVarType($var): string
@@ -1377,6 +1422,12 @@ class Translator extends \PhpAot\Core\Translator
             $name = '';
         } elseif ($expr->name->getType() === 'Name') {
             $name = $this->parseIdentifier($expr->name);
+            // 在预处理阶段检测到函数声明，但是未定义，说明在当前文件，但是顺序错误
+            if (isset($this->functionDeclInFile[$name])
+                and $this->functionDeclInFile[$name] === $this->file
+                and !$this->isNativeFunction($name)) {
+                $this->redoAfterDeclare[$name] = true;
+            }
             if ($this->isNativeFunction($name)) {
                 return self::PREFIX . $name . '(' . $this->parseCallArgs($expr->args, $name) . ')';
             }
@@ -2004,9 +2055,20 @@ class Translator extends \PhpAot\Core\Translator
         return $var . ' ^= ' . $this->parseIdentifier($node->expr);
     }
 
-    private function parseMagicConstFile(mixed $expr): string
+    private function parseMagicConst(mixed $expr): string
     {
-        return '"' . $this->escapeString($this->file) . '"';
+        switch ($expr->getType()) {
+            case 'Scalar_MagicConst_Dir':
+                return '"' . $this->escapeString($this->dir) . '"';
+            case 'Scalar_MagicConst_File':
+                return '"' . $this->escapeString($this->file) . '"';
+            case 'Scalar_MagicConst_Line':
+                return $expr->getStartLine();
+            case 'Scalar_MagicConst_Function':
+                return '"' . $this->escapeString($this->functionDef->name) . '"';
+            default:
+                abort($expr);
+        }
     }
 
     private function parseForeach(Node $node): string
@@ -2173,11 +2235,6 @@ class Translator extends \PhpAot\Core\Translator
         return 'php::include(' . $this->parseIdentifier($expr->expr) . ')';
     }
 
-    private function parseMagicConstDir(mixed $expr): string
-    {
-        return '"' . $this->escapeString($this->dir) . '"';
-    }
-
     private function parseBreak(mixed $v): string
     {
         if (!$this->inLoop and !$this->inSwitch) {
@@ -2467,11 +2524,6 @@ class Translator extends \PhpAot\Core\Translator
         return 'php::getStaticProperty(' . $this->identifierToStr($expr->class) . ', ' . $this->identifierToStr($expr->name) . ')';
     }
 
-    private function parseMagicConstLine(Node $expr): int
-    {
-        return $expr->getStartLine();
-    }
-
     private function parseThrow(mixed $expr): string
     {
         if ($expr->expr->getType() != self::EXPR_VARIABLE and $expr->expr->getType() != self::EXPR_NEW) {
@@ -2574,7 +2626,7 @@ class Translator extends \PhpAot\Core\Translator
         $this->nativeConstants[$name] = $constInfo;
     }
 
-    private function hasConstant(string $name)
+    private function hasConstant(string $name): bool
     {
         return isset($this->nativeConstants[$name]);
     }
@@ -2607,4 +2659,152 @@ class Translator extends \PhpAot\Core\Translator
     {
         return $var->getType() == self::EXPR_VARIABLE and $this->hasVar($var->name) and $this->getVarType($var->name) == self::TYPE_ARRAY;
     }
+
+    private function setBuildDir(string $string): void
+    {
+        $this->buildDir = $string;
+        if (!is_dir($this->buildDir)) {
+            mkdir($this->buildDir, 0777, true);
+        }
+    }
+
+    public function prepare(string $file)
+    {
+        $phpCode = $this->loadFile($file);
+
+        $this->climate->info('prepare: ' . $this->file);
+        $parser = (new ParserFactory())->createForNewestSupportedVersion();
+        $ast = $parser->parse($phpCode);
+
+        $traverser = new NodeTraverser;
+        $prettyPrinter = new PrettyPrinter\Standard;
+        $traverser->addVisitor(new Visitor());
+        $stmts = $traverser->traverse($ast);
+
+        foreach ($stmts as $v) {
+            $type = $v->getType();
+            switch ($type) {
+                case 'Stmt_Namespace':
+                    $this->prepareNamespaceDef($v);
+                    break;
+                case 'Stmt_Class':
+                    $this->prepareClassDef($v);
+                    break;
+                case 'Stmt_Function':
+                    $this->prepareFunctionDef($v) . PHP_EOL;
+                    break;
+                case 'Stmt_Const':
+                    break;
+                default:
+                    $this->fatalError($v, 'Unsupported statement: ' . $type);
+                    break;
+            }
+        }
+
+        $nodeFinder = new NodeFinder();
+        $functionCalls = $nodeFinder->findInstanceOf($ast, Node\Expr\FuncCall::class);
+
+        foreach ($functionCalls as $call) {
+            if ($call->name instanceof Node\Name) {
+                $name = $call->name->toString();
+                $this->functionCallInFile[] = [
+                    'name' => $name,
+                    'file' => $this->file,
+                    'line' => $call->getLine(),
+                ];
+            }
+        }
+    }
+
+    private function prepareFunctionDef(Node $v): void
+    {
+        $name = $this->getFunctionName($v);
+        if ($this->stubFile) {
+            $this->nativeFunctions[$name] = $this->parseFunctionDeclaration($name, $v);
+        } else {
+            $this->functionDeclInFile[$name] = $this->file;
+        }
+    }
+
+    private function prepareNamespaceDef(Node $node): void
+    {
+        $this->namespace = $this->parseIdentifier($node->name);
+        foreach($node->stmts as $v2) {
+            $type2 = $v2->getType();
+            switch ($type2) {
+                case 'Stmt_Class':
+                    $this->prepareClassDef($v2);
+                    break;
+                case 'Stmt_Function':
+                    $this->prepareFunctionDef($v2) . PHP_EOL;
+                    break;
+                case 'Stmt_Use':
+                case 'Stmt_Const':
+                    break;
+                default:
+                    abort($v2);
+            }
+        }
+        $this->namespace = '';
+        $this->uses = [];
+    }
+
+    private function prepareClassDef(Node $v): string
+    {
+        $this->class = $this->parseIdentifier($v->name);
+        $code = '';
+        foreach($v->stmts as $v) {
+            $type = $v->getType();
+            switch ($type) {
+                case 'Stmt_ClassConst':
+                case 'Stmt_Property':
+                    break;
+                case 'Stmt_ClassMethod':
+                    $code .= $this->prepareFunctionDef($v) . PHP_EOL;
+                    break;
+                default:
+                    abort($v);
+            }
+        }
+        $this->class = '';
+        return $code;
+    }
+
+    public function sortFiles(array &$list): void
+    {
+        foreach ($this->functionCallInFile as $k => $call) {
+            if (!isset($this->functionDeclInFile[$call['name']])) {
+                unset($this->functionCallInFile[$k]);
+            }
+        }
+        $sorter = new FileSorter($this->functionDeclInFile, $this->functionCallInFile);
+        $sortedFiles = $sorter->sort();
+
+        foreach ($list as $file) {
+            if (!$this->isStubFile($file) and !in_array($file, $sortedFiles)) {
+                $sortedFiles[] = $file;
+            }
+        }
+        $list = $sortedFiles;
+    }
+
+    private function isStubFile(string $file): bool
+    {
+        return str_ends_with($file, '.stub.php');
+    }
+
+    private function loadFile(string $file): string
+    {
+        if (!file_exists($file)) {
+            throw new \Exception('File not exists: ' . $file);
+        }
+        $phpCode = file_get_contents($file);
+        if (!$phpCode) {
+            throw new \Exception('Can not read file: ' . $file);
+        }
+        $this->file = realpath($file);
+        $this->dir = dirname($this->file);
+        $this->stubFile = $this->isStubFile($file);
+        return $phpCode;
+    }
 }